A Chrysler Hemi engine is a series of V8 internal combustion engines built by
Chrysler that utilize a hemispherical combustion chamber. Generally, a hemispherical combustion chamber (i.e., approximately bowl-shaped) allows the valves of a two valve-per-cylinder engine to be angled rather than side-by-side. This arrangement creates more space in the combustion chamber roof for the use of larger valves and also straightens the airflow passages through the cylinder head. These features significantly improve the engine's airflow capacity, which can result in relatively high power output from a given piston displacement. Chrysler has incorporated Hemi engines in many different vehicles for decades. Some modern Chrysler vehicles which incorporate (a modified version of) Hemi engines include the 2004 Dodge Ram and Dodge Durango; the 2005 Chrysler 300C, Dodge Magnum R/T and Jeep Grand Cherokee; the 2006 Dodge Charger R/T; and the 2009 Dodge Challenger R/T.
Like other engines, the Hemi engine operates by a four-stroke combustion cycle, i.e., an intake stroke, a compression stroke, a combustion stroke and a exhaust stroke as known by one of ordinary skill in the art. During this cycle, the valve spring is repeatedly compressed as a corresponding valve repeatedly opens or closes an intake or an exhaust channel. Over time, the valve spring may need to be replaced. Alternatively, a user may simply wish to upgrade a valve spring to increase performance of a vehicle.
Although Hemi engines are known to enhance performance of vehicles elative to conventional engines, maintenance of such engines can be difficult, time-consuming and/or laborious. For example, in order to remove and replace valve springs, the mechanic typically must first remove the cylinder heads or the entire engine from the vehicle. The process is time-consuming and labor-intensive and increases the overall cost of valve spring replacement tremendously.